Ultra-high voltage (UHV) circuits, such as control ICs for AC/DC power conversion, often need a means for self-biasing and/or start-up from a high-voltage DC supply. Ultra-high voltage start-up for AC/DC control of integrated circuits (IC) has typically been implemented using either a discrete high-value resistor placed on the printed circuit board (PCB) or by a normally-ON ultra-high voltage transistor, either integrated in the IC or as a discrete component on the PCB.